<form class="form">
  <div class="content">
    <p align="center">Enter your OTP Code</p>
    <div class="inp">
    <input maxlength="1" class="input" type="text" placeholder="">
    <input maxlength="1" class="input" type="text" placeholder=""> 
    <input maxlength="1" class="input" type="text" placeholder=""> 
    <input maxlength="1" class="input" type="text" placeholder=""> 
    </div>
    <button>Verify</button>
  </div>
  
</form>
<style>
/* From Uiverse.io by reshades - Tags: OTP, form, verify, Verification */
.form {
  display: flex;
  flex-direction: column;
  gap: 10px;
  background: #333333;
  border-radius: 5px;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
  backdrop-filter: blur(8.2px);
  -webkit-backdrop-filter: blur(8.2px);
  border: 1px solid #fff;
  width: 17em;
  height: 12em;
}

.content {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: auto;
  margin-bottom: auto;
}

.form p {
  color: #fff;
  font-weight: bolder;
}

.inp {
  margin-left: auto;
  margin-right: auto;
  white-space: 4px;
}

.input + .input {
  margin-left: 0.5em
}

.input {
  color: #fff;
  height: 2em;
  width: 2em;
  float: left;
  text-align: center;
  background: #00000000;
  outline: none;
  border: 1px #fff solid;
  border-radius: 5px;
  transition: all 0.6s ease;
  font-size: larger;
}

.input:focus {
  outline: none;
  border: 1px #fff solid;
}

.input:not(:placeholder-shown) {
  background-color: #fff;
  width: 1em;
  height: 1em
}

.form button {
  margin-left: auto;
  margin-right: auto;
  background-color: #00000000;
  color: #fff;
  width: 8.5em;
  height: 2.3em;
  border: #fff 0.1em solid;
  border-radius: 5px;
  transition: all 0.5s ease;
}

.form button:hover {
  background-color: #fff;
  color: #000
}

</style>
